Inductance coil



iiletented May 18, 1926.

rg You #mi are. i -e si i l fr essere? 'hSl PATENT FFC.

FIP-All I.. JDD AND ETHELBERT D. PlTT, GF NEW YORK, N. Y., ASSIGNRS, BYDI- kAND ASSGNMENTS, T CURKOID CORORJLIQN, 0F NEXV YDRK, N. Y.

rirnocrarrcn corr.

.application led November '.lhis invention relates to an inductancecoil7 and has particular reference to one adapted for use With radiotelephone and telegraph transmitting and receivingl devices, andcircuits tor electric magnetic induction.

in object of the invention is to providea method of Windingl inductancecoils Which will produce a better and more elilective distribution o'lthe magnetic iield ot the coil.

rnother object is to improve generally the etliciency ot inductancecoils Where high ciencies are necessary; especially in regard to thewindings and the cieposition thereol so as to eliminate to as great anextent possible, what is termed end capacityl; and so as to increase toa maximum the volume of' inductive capacity oll the coil in relation tothe size and length of Wire used.

Another object is to provide a loosecoupling with adjacent inductancecoils'and thereby provide less distortion of the transmitted or receivedelectrical current.

Another object is to reduce to a minimum the distributed capacity in theinductance coil.

Aanother object is to provide an inductance coil ot compact torni, withno end capacityj with a comparatively great volume ot inductive capacityrelation to the and ength ot Wire used, and with a better and fioreeffective distribution oi the magnetic ld ot the coil than hasheretofore been ossible,

rlhese and other objects and advantages of our invention are set forthin the 'following description, taken in connection with the accompanyingdrawings. life disclose herein the best form or our inductance coil non7known to us; but this torni is to be taken as merelytypical of numerousconstructions in Which the principle ot our invention may be embodiedand we reserve the right to make changes in the shape7 size andarrangement or" parts or the character ot the materials used, to thefull extent indicated by the general or broad meanings of the terms inwhich the claims are expressed.

ln the drawings:

Figure l is a front view of our invention as mounted for connection withradio telephone and telegraph transmitting and receiving circuits.

Figure 2 is a partial section taken on the line lb oi' Figure l.

Figure 3 shows the geometric development ot the form ol' the coils.

ris shoivn in Figures l and 2 the devicl comprises an ecccntrically laidseries ol in-` sulated copper magnet Wire coils l hold Within a ringtraine 2 or any suitable dielectric material. The terminals ll areconnected. to the conductive terminal posts o and set in the dielectricmounting 3 ot the coil trame Q. rihe terminal post 5 is in the 'form ota plugja Ad the terminal post (i is in the form of a soclret so that thecorrect polarity ot the coil may always be maintained in relation to theelectric circuit of which it becomes a part.

The coil. may be laid or wound with a single layer of loops or in aplurality of la l ers as shown, dependent on the radio wave length it isdesired that the coil shall be capable ot receiving.

rllhe geometric torni or the coil is that of a basis of curtateepitrochoids as shown in Figure 3 Where the separate loops of the coil lare shown in development by la Within the circle 2a. rllhe loops la arelgenerated by the rolling oit circle 8 with its extended radius 9 on theexterior circumference or circle l0, this rolling being effected Withoutslipping. rlhe extension or the radius 9 ot circle 8 is equal to thedistance from the center of 8 to 2a. T ie direction cit {generation isindicated by arrow heads. lli/*hilo in the actual practical operation ofWindingl the coil on a machine developed :tor that purpose it may not bepossible to Wind so accurately as to prevent some sligp say or S inrolling; on l0, yet it has been round that the individual loops or coill are esseir tially of the exact torni ot a curtate epitrochoid or it a.curtate hypotrochoid of circle 8 be rolled on the interior circumferenceo'l circle lO.

lllle have found by actual experiment that the method of Winddng` shownenables a considerable broadening of the magnetic field o'l the coil incomparison with ua more or less tightly Wound coil such as the singlelayer solenoid banlr wound, or even the Well known honeycomb orduo-lateral types ot inductance coil.

With the particular Jlorm ot Winding shown, the magnetic i'ield isbroadened and results in the reduction to the absolute minimum of thedistributed capacity ot the coil.

The i'nctliod of winding' Shown makes clem' the 'fact 'that tlm laatlayer wound will lie directly m llic magnetic flux field of l'lic lieii'inductive Strength is tliei'cbjy onlizmi'cfl. This eiinunccu'icn ofinductivo sti'cngg'li on :iblcs a "locsc" typo of coupling' lo be Ulu--primari l. As mi article ci iiiumx'ncluie :in iiiluclmice coll livvlug:L 'plurality cr" mop windings ci' a single coniiiiuons craiilxlczrn'arranged laterally cccci'ic ou@ with tlc other.

2. The combination in a coil 'loi' iimgnclic induction, of f1 pluralityof loop wiin'li'l of u singley continuous conductor m.' long/2 which aregcnci'atcd iu thc geomelric form of :1 ti'oclioicl,

3. AS un article of nimm. L :m cluctmice coil lim'ing a plui'ali'ty olllayers of loop windings oi a Single coiil'nuouss con- (luctm', .:icliliyci' consisting' 0i u plurality of windings .fu'rnngi'Q-i'l laterallyecccul'i'ic mi@ with the other.

Ll. AS im article of manufactui'c au iii luc lance, coil com ijli'iseilm s. 'plum'. ity nl' lujyci'fv; 0i lomp windings of zi single connimwuscm1- (luctoi, che wiuiinlg'fs i1 @zich lzijfci' hiring; uw ccni'ic 0110willi lic olxci' :mil lli/J lijui's being' coiiccni 'c with c: l1clilxcx'. l

fai' un um l i a ici', lm conccmi'il' FEAR-@55 L. JUDD. ETHELBERT D.PTl.

